Classifier



Jan. 10, 1928. I 1,655,577

A. H. STEBBINS CLASSIFIER Filed Dec. 24. 1926 2 Sheets-Sheet 2 HVVENTORXA TTORNE Y Patented Jan. 10, 1928.1

, UNITED STATES T E T orrllce.

ALBERT H. s'rnisnrns, OF LOS nnennnsfcnninonnrn.

' CLASSIFIERi Application-filedDecember24, 192 SerialNo. 156,847.

This invention relates to classifiers of the Fi 1 is a side elevation ofa classifier contype in which the materials passing downwardlywithm atreatment chamber'are subjected to the action ot air currents adapted toseparate the finer coarser particles. V 7

In employing classifiers of this general type it is dihicult to effect athorough'treatment of the materials through the use of air blasts alone,or through air. exhausts alone, and if the materials tobe separatedrelatively fine it is necessary to subject them time and time again tothe action of the separating air currents.

The present invention is therefore directed particles from the to amultiple treatment classifier which is so constructed thatmaterialspassing downwardly through the treatment chamber are subjectedrepeatedlyjto the separation action of different aircurrents to extractthe lighter from the. heavier "particles, and also to a construction foremploying both suction and blast forces in effecting the separation ofthe materials.

One or the features of the present invention resides ina classifiercasing which is adapted to be supported in an upright position so, thatthe materials to be treated may pass downwardly "therein under theinfluence of gravity, and in means for directing air jets across thepath'ot the materials from the opposite sides of the casing 'to deflectthe materials back and forth from one side of the casingto the other asthey move downwardly therein.

vAnother feature of the invention resides in means for removing thelighter particles that remain suspended in the air -from the casing byexhausting them therefrom in a direction at right angles to theair jetaand also in settling chambers that are adapted to return to the casingthe particles that settle in said chambers. i a

Another feature of the invention resides in the novel arrangement ofparts for supplying air under pressure to the treatment chamber and forexhausting air therefrom, and also 1n the means formtroducmg air fromthe atmosphere into the casing.

t invention.

' Other features of the invention'and novel HFigq2 is line 22 of Fig 1;1

Fig. 4 on an enlarged scale is a 'perspec- 'tive viewv ot the upperportion of the classifier shown in Fig. 1; the walls of the classifierbeing partly broken away to show the internal construction; and

Fig. 5 is a sectional View taken ontheline 5- 5 ot'Fig. 2.- 1

In the emb diment of the invention shown the separation of the materialsis effected in.

vthecentralcasing 10 which is adapted tobe supported in an uprightposition so that the materials to be treated will pass downwardly withinthe casing under the influence of gravity. The casing 10 183 shown assquare in cross section and as having one pair of opposite walls 11- anda second pairof opposite'walls 12. The casing is preferably made square,or rectangular inscross section-in order to better accommodate the} airblast pipes 13 which extend lengthwise ofltheside walls 11:0f thecasing, 'and'to' accommodate by adjusting th s d combination of parts inaddition to the above will be hereinafter described in connection withthe accompanying draw ngs, WlfllCll illustrate one good practical formof the In drawingsthe dust extracting chambers 14 which are arrangedlengthwise of the side walls12 of e Casing, as will be hereinafter morefully explained; i I j Thematerials to be treated may bedoli.vered-tothe upper endof the casing lOby the feed hopper 15 havingthe central discharge opening 16; and-the rate at which the materialsare supplied tothe. treatment chamber by the hopper 15 may becontrolledgate 16. j A'r under pressure is supplied to the air blast pipes'18 by ablast .fan 'or the like 17,

and the upper ends otthe pipes 13:are connected tothe fan 17byfthebran'ch pipes 18. asbest, shown in Fig. 3. The'strength of the airsupplied to the blastpipes '13 may be controlled by I adjusting thesliding .gate 19 (see Fig.1);

As thematerlalsbeing treated pass down- ,wardly within the casing 10they are deflected back andf forth from" one side wall of the casing tothe other by air jets which-j are directed transversely of thefl'casing10 i from the opposite side walls 11 thereof, and tothis-end in theconstruction shown each sidewall 11 of the casing is provided with alarge number of slots 0: air discharge new 11 of the casing between apair of adjacent nozzles. As result of the construction just describedit will be seen that the materials downwardly within the treatment cabeing treated will be detlected back and forth a number of times whilethcv pass The number of air dis har 'e nozzles 29 can gate 23 ployed,and the length of the treatment cas ing will depend largel'yupon thenature of the materials being treated. If the classifier is designed totreat relatively coarse materials a comparatively few discharge zles maysutlice to etl'ect the d ration, butit the classifier is to he toseparate fine, dust-like I necessary to subject the mate i time and timeagain to the separating 5M 1 a ot the air blasts delivered by thenozzles 20.

The heavier materials which pass downwardly within the casing 10 to thelower end thereof will be collected in the discharge spout 22 froinwhichthey may be withdrawn from time to time by opening the discharge It. isnecessary to remove from the casing 10 the liner particles that remainsuspended within the air, and this is accomplished, in accordance withthe present invention, by providing a large number of air dischargeopenings 24- within the opposite side walls 12 of the casing. It isdesirable to introduce the air withdrawn from the casing 10into'se'ttling chambers in order thatit will be the larger particlesthat may escape through the openings 2&- will have an opportunity tosettle, and to this end the settling com-- partmentsle above mentionedare provided,

These compartments are conveniently constructed by providing theclassifier casing with the side walls 25which extend laterally from thetreatment casing 10 'to the air e2;- haust pipes 26 mounted at each sideof the casing 10 in spaced relation to this casing, as best showninFig. 1. lVithin the charm hers 14 formed between thespaced side walls 25are mounted the inclined floor plates 27 between which are formed thesettling com- I partments and the arrangement of these floor till platesis such that the materials that settle within the compartments willslide down these inclined plates to be returned to the casing lOforfurther treatment.

The air exhaust pipes 26 above mentioned are preferably made square orrectangular in cross section, as will be apparent from Fig. 4, andair isexhausted fromeach of these pipes by connecting the upper end of eachthat the suction produced within the pipes will cause the air in whichthe lighter particles may be suspended to pass through the openings 24:into the settling chambers t l, and this air will travel upwardly withinthe settling chambers to escape therefrom through the discharge slots 29into the exhaust pipes 26'.

It air is exhausted from the treatment casing 10 by the suction pipes 26more rapidly than it is supplied to this casing by the blast pipes 13 apartial vacuum may he produced within the casing 10, which willmaterially ajti ect the separating operation. Y It. may therefore bedesirable to provide means For introducing air from the atmosphere intothe casing ll) and this is accomplished, in accordance with the pres ntinvention, by the construction shown, wliercby air is led. into thesettling cmnpartments adjacent the lower end ot' each inclined floorplate 27, the ar *angementbeing such that the air introduced from theati'nosphere will pass upwardly through the materials sliding down theinclined floor plates 27, to assist in the separation of thesematerials. In order to introduce air from the atmosphere into theclassifier casing near the lower end of each inclined floor 2. an airguide plate 31 is disposed adjacent the lower end of each floor plate toprovide the air passage 32 at the under face of each plate 27, and airis ad mitted to the air passage 32 through the opposite side walls 25 ofthe casing by providing these side walls with the air inlet holes Theupper portion of each plate 31 is rounded as indicated by 3% to closethe upper end of each air passage 32; The lower end of each plate til.it will be noted, extends into an opening Qt of a side wall 12, thearrangement being such that the materials which are delivered by thefloor plate 27 to the air guide plate ill will be directed by the latterthrough an opening into the casing 10 for further treatment.

It will be apparent from the foregoing description. when read inconnection with the drawings, that air under pressu e supplied to theopposite walls ll of the casing 10 by the air blast pipes 13 to producethe air jets above described which deflect the materials back and forthas they move downwardly within the casing l0. and itwill be understoodthat the lighter particles which remain suspended in the air within thecasing 10 are withdrawn therefrom through the discharge slots 24 intothe settling compartments 14 so that the particles that settle withinthese compartments will.

lfll

at the lower ends of these be returned to the casing; 10 for furthertreatment. Such particlesfas may settle within the suction pipes 26 willcollect in the discharge hoppers 35 at. the lower end thereof and fromwhichthe materialsmay be withdrawn from time to time. The air blastpipes 13 are preferably provided with the discharge openings 36 at theirlower ends so thatthese pipes may beblown out from time to time byopening the gates 37 pipes. I

' What is claimed is i 1. A classifier comprising in combinationanupright casing, means for delivering the 1 materials tobe treated tothenpper portion of the casing to pass downwardly therein under theinfluence of gravity, air blast nozzles provided alonggthe oppositesidesxo'f said casing andadapted to directair cur:

'1 rents across the casing tromgone wallto adjacent the other wa l sothat theyfwill lntersect' the path ofthe materials moving I downwardlywithin the casing fromits op.-

posite sides, and means for removing from the casing the lighterparticles that remain suspended in the air.

2. A lassifier comprising in combination,

ofwthe casing topass downwardly therein under the influnce 'of gravityt.means" for directing jets of air into the casingfr'o'm the oppositesidesthereof and arranged in" staggered relation to each other so that thematerials passing downwardly within the casing will be deflected backand forth from one side wall of the casing to the other, and means forremoving from the casing the lighter particles that remain suspended inthe air.

3. A classifier, comprising in combination,

an upright, casing, meansfor delivering the materials to be treatedto-the upper portion of the casing to pass downwardly therein, meansforintroducing jets of air into the casing from the opposite sides thereofat intervals along the path of the materials moving downwardly in thecasing to cause the air jets to intersect said path from its oppositesides, and means for exhausting air from the casing at points betweenthe adjacent air jets, i

4;; A classifier, comprising in combination, an upright casing havingfour opposite side walls,means for delivering the materials to hetreated to the upper portion of the casing to pass downwardly therein,means for introducing jets of air into the casing from one pair ofopposite side walls to cause the air jets to intersect the path of thematerials moving downwardly within thecasing, and means for removing airfrom the casing through openings formed in the second pair of oppositeside walls. e 5. A classifier comprising in combination,

delivering the I a relatively long slender casing adapted to in a pairofopposite wallsjofthe casing throughout [the length of the casingandadapted to deflect the material passing downwardlywithin the casingback andforth from oneside wall togthe other, and means for removingfrom the casing thelighter particles that remainsuspended in the air.

' 6. A classifier comprising in combination, an upright casing havingfoiiropposite side walls, means for delivering the materials to betreatedtotheupper portion of the casing 'to pass f downwardly therein, apair of air blast pipes arranged/along two of thefopj'posite walls ofthe casing and provided with air} apertures for directing air jetsinto's'aid casing from its opposite side walls and; a pair of airexhaust pipes extending lengthwise of the two remaining walls of the(13S? ing and provided with air openings; for "exhaustin airirom thecasing at points between said air jets. V r

A classifier comprising in combination, an "upright casing, means fordelivering the materials to be treated to theupper portion of the casingto pass downwardly therein under thelinfiuence of gravity, means forintroducing jets of air into the casing from the opposite sides thereofat a multiplicity of points along its length-means for forming a seriesof settling chambers along said casing and provided with inclined floorsfor directing the particles that settle in the chambers back into saidcasing for further treatment, and means for-removing from said chambersthe lighter particles that remain suspended in the air.

8. A classifier comprising in combination,

an upright casing. means for. delivering. the

materials to be treated to the upper portion of the casing to passdownwardly therein under the influence of gravity, means for introducingjets of=air into the casing to intersect the path ot'the materialsmoving downwardly within the casing, and means for exhausting air fromsaid casing through aside wall thereof in a direction at rightangles'tothe path of the airjets, including settling chambers along said casingand provided with inclined floors for directing the particles thatsettle in the chambers back into the casing for further treatment.

9. A classifier comprising in combination, an upright casing, means fordelivering the materials to be treated to the upper portion of thecasing to pass downwardlytherein under the influence of gravity, meansfor introducing jets of air into the casing from the opposite wallsthereof to intersect the path of the materials moving downwardly withinthe casing, and means for exhausting under the influence of gravity,means for introducing jets of air into the casing to intersecttlie pathof the materials moving downwardly within the casing, means forexhausting air from the casing through a side wall thereof in adirection at right angles to the patlrof the air j ets, includingsettling chambers along said casing and provided with inclined floorsfor directingthe particles that settle in the chambers back into thecasing, and means for intrcducing air mto the casing at the lower end ofeach inclined floor to pass upwardly through 'thematerialssliding alongthe floors.

11, A classifier comprising in combination, an upright casing, means tordelivering the materials to be treated to the upper portion of thecasing to pass downwardly therein under the nfluence of gravity, meansfor introducing jets of air into the casing from a pair of opposite sidewalls thereof to intersect the path of the falling materials,

means for exhausting air from the casing through opposite side wallsthereof in a direction laterally to the air jets, including settlingchambers along" said casing and provided with inclined floors fordirecting the particles that settle in the chambers back into the casingfor further treatment, and

means for introducing air from the atmosphere into the casing at amultiplicity of points lengthwise of the same.

12. A classifier comprising in combination,

a four-sided casing constructed to be supported in an upright positionand provided with an air conduit extending along each side of thecasing. means for delivering the materials to be treated to the upperportion (7f the casing to pass downwardly therein under the influence ofgravity, two of said conduits positioned at the opposite sides of saidcasing being. provided with a series er air apertures disposedlengthwise of the casing to produce air jets across th e'casing tointersect thepath of thefalhngmaterials,

means for delivering air under pressure to the .two conduits, saidremainmg pair of conduits being provided with a series of aperturesdisposed lengthwise ofthe casing for exhausting air from the casing, andmeans for exhausting air from the two cenduits last mentioned.

In testimony whereof, I have signed my name to this specification.

ALBERT H. STEBBINS.

